Brush construction



April 11, 1967 E NELSON I 3,312,993

BRUSH CONSTRUCTION Filed. Jan. 11. 1965 I 2 Sheets-Sheet 1 I l 3 U, M

I \.-:l).' i 31 H '2 T n I J 8 n 1% I {MM u INVENTOR BROOKS E. NELSONATTORNEYS April 11, 1967 B. E. NELSON 3,312,993

'BRUSH CONSTRUCTION Filed Jan. 11, 1965 2 sheetssheet 2 v INVENTOR.WOO/(SE. NELSUN BY .15 F; .25 dmwafimzg/ ATTORNEYS United States Patent3,312,993 BRUSH CONSTRUCTION Brooks E. Nelson, Chagrin Falls, Ohio,assignor to The Osborn Manufacturing Company, Cleveland, Ohio,acorporation of Ohio Filed Jan. 11, 1965. Ser. No. 424,542 Claims. (Cl.180) This invention relates as indicated to a novel brush construction,and more particularly to power driven rotary brushes in which the brushbristle material is assembled or grouped into a plurality of bundles ortufts. Certain subject matter disclosed but not claimed herein isdisclosed and claimed in my copendin-g application Serial No. 585,842,filed October 11, 1966, and in my copending application Serial. No.494,688, filed October 11, 1965, now Patent No. 3,289,235.

It is, of course, quite old preliminarily to secure bristles intoseparate tufts of various sizes and shapes prior to mounting orinserting such assembled tufts into different types of brush backs orholders. When exceptionally stifi or brittle brush fill material isemployed which may fracture when sharply bent about a retaining memberthere are obvious advantages in securing such brush fill material inother ways which do not involve sharp flexing of the same. Particularlyin the case of small end brushes, the manufacturer encounters theproblems of uneven fill distribution, the dii'ficulty and expense oftrimming the brush to a true flat face, and the excessive stressesplaced upon the retaining members when heavy wire brush bristle fillmaterial is employed and bent to U-shape for retention within the usualcup shaped holder.

It is accordingly an important object of my invention to provide a novelbrush construction wherein a plurality of brush bristle tufts arepreliminarily assembled and secured by means of encircling bands orclips, without excessive flexing of the bristles, and the tufts th-usproduced are then inserted and retained within an appropriate holder orbrush back.

Another object is to provide such tufts, the shapes of which may bemodified through corresponding modifications of the shapes of theretaining bands or clips to produce brush faces having desiredcharacteristics.

A further object is to provide novel means for securing such brush tuftswithin the backs or holders through interengagement of the sides of suchbacks or holders with the bands or clips which thus directly encircleand grip the individual tufts of brush fill material.

Still another object is to provide power driven rotary brushes in whichthe brush material is in the form of a plurality of closely assembledtufts which aiford an even distribution of the brush bristle fill aswell as an even, true brush face.

Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said inventionthen comprises the features hereinafter fully described and particularlypointed out in the claims, the following description and the annexeddrawing setting forth in detail certain illustrative embodiments of theinvention, these being indicative, however, of but a few of the variousways in which the principle of the invention may be employed.

In said annexed drawing:

FIG. 1 is a side elevational vew of a power driven rotary brush producedin accordance with the present invention;

FIG. 2 is an end View of the brush of FIG. 1;

FIG. 3 is a longitudinal section through the brush of FIG. 1 taken onthe line 33 on FIG. 4;

FIG. 4 is a transverse section taken on the line 44 on 3,312,993Patented Apr. 11, 1967 ICC 2 FIG. 3, but before turning in the lip ofthe cup shaped holder;

FIG. 5 is a side View of an individual brush tuft adapted to beassembled into the brush construction of FIGS. 1-4 inclusive; 7

FIG. 6 is a butt end view of the brush bristle tuft assembly of FIG. 5;

FIG. 7 is a longitudinal section through a power driven rotary end brushsimilar to that of FIG. 3 but comprising a plurality of assembled tuftsforming a solid or closed end face rather than the circular or open endface of FIG. 2, such section being taken on the line 7-7 on FIG. 9;

FIG. 8 is a view of the end face of the brush of FIG. 7;

FIG. 9 is a transverse cross-section taken on the line 99 on FIG. 7;

FIG. 10 is a side view of a brush bristle tuft used in the assembly ofthe FIG. 7 embodiment of the invention;

FIG. 11 is a butt end view of the tuft of FIG. 10-;

FIG. 12 is a side elevational view of a length of brush stripcomp-rising a plurality of tuft assemblies secured within an appropriateelongated channelform back;

FIG. 13 is a transverse section taken on the line 1313;

FIG. 14 is a longitudinal section taken on the line 14,14 0n FIG. 12;

FIG. 15 is an end View of a wheel type power driven rotary brush whereina plurality of brush tuft assemblies are secured in generally radiallyoutwardly extending positions; and

FIG. 16 is a generally diametral section taken on the line 16-16 on FIG.15.

Referring'now more particularly to said drawing and especially FIGS. 1-6inclusive thereof, the embodiment of the invention there illustratedcomprises an end brush having a metal holder in the form of a cupportion 1 with an axially extending stem or spindle 2 adapted to bereceived and gripped by the chuck of an appropriate power driven tool.Crimped wire brush fill material 3 is retained Within such cup portionand extends outwardly therefrom to provide a generally fiat circularbrush face 4 composed of the outer tip ends of such wires. In the formthus illustrated, the brush fill material is actually in the form ofthree separate tufts or bundles 5, 6 and 7 individually clipped togetherby sheet metal clips or bands 8, 9 and 10 encircling the basal portionsof the respective bundles. As best shown in FIG. 5, each such band maybe provided with an upstanding portion 11 which is deformed locally tocompress the corresponding region of the tuft or bundle. It will thus beseen that the basal portion of each of the three tufts is of generalarcuate segmental or pie shape form, with the inner tip compressed orindented by means of such upstanding portion 11. The bristles of each:bundle are carefully cut to length so that a true normally flat endface is afforded. Three of such clipped together bundles are assembledwithin the cup shaped holder 1 as shown in FIG. 4 to form the circularbrush face 4 (FIG. 2), and the lip 12 of the cup is turned in to overlieand secure the upper edges of the several bands 8, 9, 10 as shown inFIG. 3, the relatively short protruding inner end portions 13 of thebristles engaging the inner bottom of the cup. In this manner, thebundles of brush material are firmly secured and held within the cupshape holder. An adhesive such as an epoxy resin cement may also beprovided in the bottom of the cup if desired. The upstanding portions 11may be apertured as at 14 to assist in handling the individual tuftsduring the die forming and assembling operations.

End brushes produced in the manner described above have severalpractical advantages. In the first place, by

a banding the individual bundles of brush material, the handling of suchbrush material during manufacture is much simplified, crimped wirebristle material being notoriously difiicult to manage when handledloose. The individual bands also permit shaping of the component bundlesor tufts to desired contour, in the example illustrated and describedsuch tufts presenting an, arcuate outer contour, radial sides and anarcuate inner contour, thereby, when assembled within the holder,producing the circular hollow end face desired. Since the individualtufts are formed of bristles of the proper length and such bristles areclamped against shifting, the final brush assembly requires little or notrimming or grinding in order to obtain the desired flat end face.Hollow face end brushes are frequently preferred because the centralbristles of rotary end brushes perform relatively little active brushingon the work surface and most of the wear is accordingly on the outerbristles. It will be appreciated that the number of bundles thusassembled within a single cup shape holder is to some extent a matter ofchoice, but it has been found that three such bundles are ordinarilypreferred in the usual size end brush.

New referring to FIGS. 7-11 inclusive, a generally similar end brush isshown in which, however, the individual bundles of brush material 3 aresecured by bands or clips 15, 16 and 17 which are not provided with theupstanding portions 11; in consequence, the brush fill material producesa solid flat circular end face 18 as indicated in FIGS. 8 and 9. Theends of each band or clip may desirably be diagonally offset as at 19and the upper and lower edges of the clip may :be slightly inwardlycrimped by the forming dies. Such diagonally overlapping ends of theindividual bands or clips are preferably located at the outer arcuatesides of the latter, and the several tufts or bundles are received andretained within the cup shape holder in the same manner as thatdescribed above. End brushes of this type may be assembled with greatrapidity and yet achieve strong construction which stands up well inuse. These is no opportunity for the fill to shift during manufactureand the resultant brush has excellent balance, uniform fill distributionand proper trim.

Referring now to FIGS. l2, l3 and 14, a length of brush strip is thereillustrated comprising a sheet metal channelform brush back 20 havingtufts or bundles of brush material 21 secured therein. Each such bundleof brush material is preliminarily secured adjacent its basal end bymeans of an encircling clip or band 22 which may be compressed or formedto general elongated rectangular shape as best shown in FIG. 14 forreception within channel back 20. Ordinarily such clip or band 22 willbe slightly spaced from the extreme inner end of the tuft so that ashort basal portion 23 of the latter will project therebeyond and engagethe inner bottom surface of the channel back. An appropriate adhesivesuch as an epoxy resin may be applied to such inner end portions 23 ifdesired to assist in securing the same to the brush back. While thechannel lips may be slightly turned in to secure the clips and thus thetufts within the channel, it is normally preferred instead to indent thechannel sides at 24 to overlie the outer edges of the clips 22 to securethe tufts against removal from the brush back, such indentationsextending parallel to the channel lips. Additional indentations 25 maybe provided in the channel sides normal to the lips of the latter andspaced inwardly therefrom to. produce slight projections between theclips of adjacent tufts to ensure against any possible shifting of thelatter longitudinally of the channel back in use. Brush strip of thisnature will ordinarily be utilized in straight or long lead helicallengths for mounting on rotatable hubs generally parallel to the axis ofrotation thereof. Such brush strip is adapted to automatic manufacturein continuous lengths and normally requires little or no trimming inview of the accurately dimensioned tufts of which it is composed.

7 same manner described above in connection with the FIGS. l2-14embodiment and are held against outward withdrawal by indentations 31and 32 which overlie the outer edges of the clips 22. The inner edges ofsuch clips may be seated against shoulders 33 and 34 of the circularchannel back with the basal portions of the tufts fitting within anarrower inner bottom portion 35 of the channel. Narrow radialindentations 36 and 37 are provided intermediate the clips of adjacenttufts to prevent circumferential shifting of the tufts in use and so tokeep the brush in proper balance.

7 While crimped wire brush employment .in the bmshes of the presentinvention as above described, it will nevertheless be appreciated that awide variety of different brush fill materials may be utilized including.hard straight plastic beaded wire (see Patent No..3,0 90,061), plasticcoated wire, tampico fiber, plastic monofilaments such as nylon and thelike. In certain instances, particularly when utilizing relatively hardbrittle brush bristle material, it may also be advantageous toimpregnate the butt portions of the tufts which are encircled by theclamping bands or clips with a suitable elastomeric material such asfoamed polyurethane, for example.

It will be seen from the foregoing that a novel form of brush.construction has been provided which is not only adapted to high speedassembly and manufacture, with, consequent reduction in cost, but whichis also superior in uniformity of fill, balance, and brush face trim..

.Other modes of applying the principle of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims or'the equivalent of suchbe employed.

I therefore particularly point out and distinctly claim as my invention:

1; An end brush comprising a circular holder and a plurality of parallelbundles of brush material secured therein, each said bundle comprising aquantity of parallel bristles wiht the basal portion of each bundletightly encircled by a band around'the same, the basal portions of' saidbundles substantially entirely filling said holder, and centrallylocated means acting to deflect adjacent bristles outwardly of saidholder to form an annular brush face of enhanced bristle density.

2. The end brush of claim 1, wherein said centrally located meanscomprise upstanding portions on said bands deformed toward the outerperiphery of said holder.

3. The end brush of claim 1, wherein said bands each define a sector ofsuch circle.

4. A power driven rotary end brush comprising a circular cup shapedholder and a plurality of individual parallel bundles of brush materialsecured closely to gether therein and extending therefrom to provide acomposite brush face, each said bundle being encircled and held tightlycompacted adjacent its inner end by a rigid band around the samedefining a sector of such circle, thereby filling said holder andproviding a circular brush face, the inner apex of each said sectorshaped band being deformed to afford a central region in said holderdevoid of brush material, whereby said circular brush face has a hollowcenter.

fill material is suitable for 5 5. The end brush of claim 4 wherein theinner apex of each said sector shaped band is provided with anupstanding portion which is deformed toward the outer arcuate part ofsaid band thereby locally to compress the respective bundle of brushmaterial into generally arcuate cross-section.

References Cited by the Examiner UNITED STATES PATENTS PetersonGyllenberg 15180 Benyak 15-18l X FOREIGN PATENTS Germany. Italy.

Great Britain. Great Britain.

1. AN END BRUSH COMPRISING A CIRCULAR HOLDER AND A PLURALITY OF PARALLELBUNDLES OF BRUSH MATERIAL SECURED THEREIN, EACH SAID BUNDLE COMPRISING AQUANTITY OF PARALLEL BRISTLES WITH THE BASAL PORTION OF EACH BUNDLETIGHTLY ENCIRCLED BY A BAND AROUND THE SAME, THE BASAL PORTIONS OF SAIDBUNDLES SUBSTANTIALLY ENTIRELY FILLING SAID HOLDER, AND CENTRALLYLOCATED MEANS ACTING TO DEFLECT ADJACENT BRISTLES OUTWARDLY OF SAIDHOLDER TO FORM AN ANNULAR BRUSH FACE OF ENHANCED BRISTLE DENSITY.